Magandang umaga!! If you are polite you would say"Magandang umaga po!!
'Magandang hapon.'
there are many good songs in tagalog. try these songs composed by: Freddie aguilar, yano, and other folk composers in the Philippines.
"Magandang gabi" you could also say "Magandang gabi po", "po" was included to show respect. For example "Magandang gabi sa'yo" (Good evening to you) or "Magandang gabi po sa inyo" (Good evening to...
magandang gabi.....